Diagnostic instrument



June 1 H. L. DE ZENG DIAGNOSTIC INSTRUMENT File ad August 24, 1923 INVENTOR:

" ATTORNEYS.

Patented June 1, 1926.

UNITED STATES 1, 7, 5 PATENT oFFIcE HENRY L. DE zmw, or mooans'rown, Nnw JEasriY, assreuon ro E me sunn- ARD COMPANY, or camnmr, nEw JERSEY, 'A conromirrouor NEW JERSEY.

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Application filed August 24, 1923. Serial No. 659,080.

It further relates to ahigher standardiza- 15 tion of electrically lighted diagnostic instruments, by which more rapid and accurate diagnosis may be obtained, also more accurate measurements derived.

of construction and advantage, all as will be hereinafter pointed out in the specification and claims.

For the purpose of illustrating my invenv tion, I have shown in the accompanying drawings a form thereof which is at present preferred by me, since it will give in practice satisfactory and reliable results, although it is to be understood that the various mstrumentalities of which my invention consists can be variously arranged and organized and that -my invention is not limited to the precise arrangement of these instrumentalities as herein shown and described. Y

5 In the accompanying drawings:

Figure 1.1, represents a vertical sectional view of a diagnostic instrument in the form of a retinoscope which embodies my invention, the handle portion being shown in elevation.

Figure 2, represents on an enlarged scale, a side elevation of the lamp employed.

Figure 3, represents a top plan view of Figure 2.

Figure 4, represents a cross section of a beam of light projected from a diagnostic instrument embodying my invention.

Similar numerals of reference indicate corresponding parts.

'Referring to the drawings:

1 designates my novel construction of a diagnostic instrument, the same comprising the handle 2, which is utilized to contain a battery of any conventional type, said It further consists of other novel features,

.thrcaded into the handle at 21.

handle having the light socket extension 3, mounted in the insulator 4,-around which is the clrcuit breaker nut 5. The extension 3,

is prolonged upwardly as at 6,-and inter-. nally threaded td form a socket to receive the base ofthelamp 7. 8 designates a light 60 -passageway casing supported on the outer periphery ofvthe extension 6, and having at 1ts upper end the condenser 9. The body' or plate '10, is secured to the upper portron of the casing 8, and has the sight open- 5 mg 11. 12 designates a su port for the reflcctor 13,which has the sightopening 17.

The lamp 7, has a clear globe 14, base 15 and the concentrated filament 16, and forms 'a central contact with the battery through the-conductor 18. One form of a concen trated filament is clearly-shown at 16 in Figure 2, also in the plan view of Figure 3.

The lamp socket extension member 3 is 7 screw threaded into the insulation member 4 at 20, and the insulation member 4 is screw The extension member 3 has a lamp socket 22, in-

to which the lamp is screw threaded, the lamp having the contact 25' which contacts with the conductor 18 which extends throu h the orifice in the extension 3. The lig t passage way member or cap 8 is secured to the extension member 8 by screw threads at 2 3. The circuit is made and broken by the circuit breaker not 5, which is screw threaded onto the extension 3 by the, screw threads 24:. 7

While I have preferably shown my invention in Figure 1, as having a handle adapted to carry a source of electric energy, nevertheless any other convenient type off handle may obviously be employed such as a cord attached handle for making contact wlith an independent source of electrical sup- 1 .v-

The operation is as follows: In using my invention in the form of a retinoscope, the light from the concentrated filament of the lamp, first passes through the condenser 9, to the inclined reflector 13, which directs it into the eye of thepatient, while the instrument is being held in the hand of the operator with his eye at the sight hole 11. By a artial rotation of the instrument, the proyected light ,beam is caused to travel across the pupil of the pa tient in different directions.

tients eye. This action causes a movement of the reflected light seen by the operator in the pupil of the patient. The various errors of refraction may be determined by one skilled in the art through a correct interpretation of these responsive light reflexes, as they appear in the pupil, when the projected light beam is swept across the eye of the pa- This is known as objective eye testing, and --is termed retinoscopy. It is therefore apparent that an exact diagnosis and measurement can only be obtained b the employment of an instrument whici will project an exact light beam. In prior instruments of this general character where direct illumination is employed, the light projection-has not been uniform, by reason of the fact that they were designed to utilize miniature electric lamps having nondescript types of filaments,some of them in character somewhat resembling a croquet wicket, others the letters S, and still others a hairpin, the last mentioned type being tall and narrow. None of these instruments could give the type of illumination required for making a correct diagnosis or an exact measurement in retinoseopy when using direct or unale tered illumination derived from lamps havingfilaments of this character.

In my invention this obstacle has been overcome by the employment of a novel construction and illuminating source, collocated, as hereinbefore described.

In objective eye testing by retinoscopy, it is imperative that the light shall radiate uniformly from the mirror of the retinoscope if the refractivewondition of the eye being examined is to be accurately diagnosed or measured.

In accordance with the established laws of optics, such light can only be obtained from a minute spark or spot of incandescenee. Such light cannot be derived from electric incandescent lamps having either a broad or a tall narrow filament. It can, however, be derived from an incandescent lamp having what is known as a concentrated or closely woven filament. Such a filament may be made by using a short arched spiral of tungsten wire. It will give the effect of an intense spark, or minute spot of incandescence when burning. My invention employs such a lamp in combination with the necessary optics to give a new and-superior illumination in diagnostic instruments for use in eye, ear, nose and throat work.

It will now be apparent that I have devised a novel and useful diagnostic instrument which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description, and while I have, in the present instance, shown and described a preferred embodiment thereof which will give in practice satisfactory and reliable results, it is to be understood that such embodiment is susceptible of modification in various particulars without departing from the spirit or scope of the claims or sacrificing any of its advantages.

Havin what I c aim as new and desire to secure by Letters Patent, is:

1. In a device of the character described, in combination with a handle light source, a light socket extension having a threaded connection to the handle, an internal threaded lamp socket recess in the extension, an internal orifice leading from the handle to the lamp socket recess, an external threaded portion on the extension, a light passageway casing engaging the external threaded portion, an electric lamp in the threaded lamp socket recess, a second threaded external portion, on the extensiop and a circuit breaker band on the second threaded portion adapted to make and break the electric circuit between the handle and lamp by rotation of the circuit breaker band.

2. In a device of the character described, in combination with a handle light source, a light socket extension having a threaded connection to the handle, an internal threaded lamp socket recess in the extension, an internal orifice leading from the handle to the lamp socket recess in the extension, an electric conductor 1n the internal orifice, an

external threaded portion on the extension, a light passage-way casing engaging the external threaded portion, an electric lamp in the threaded lamp socket recess having a contact and a short arched spiral filament, a second threaded external portion on the extension and a circuit breaker band on the second threaded portion adapted to engage and disengage the contact portion of the lamp and the conductor by rotation of the circuit breaker band.

HENRY L. DE ZENG.

thus described my invention, 

